The present invention relates to microscale optical devices and, more particularly, to an optical device that includes a tunable microdisk resonator with a high quality factor.
High-quality-factor resonant optical devices such as Fabry-Perot cavities have been proposed as extremely effective tools for the delicate manipulation and measurement of subtle quantum states (P Horak et al., “Possibility of single-atom detection on a chip”, Phys. Rev. A vol. 67 p. 43806 (2003); W. von Klitzing et al., “Tunable whispering gallery modes for spectroscopy and CQED experiments”, New J. Phys. Vol. 3 p. 14 (2001)). If the quality factor of such a device is sufficiently high, a single photon can interact many times with the same atom, ion or molecule so that a significant interaction can be achieved. However, to achieve such strong coupling, the optical device must be kept on resonance with a frequency that is sufficiently close to the frequency of the chosen quantum transition.
Tunable resonant microdisks have been used as filters and switches in optical communication (Konstadin Djordjev et al., “Microdisk tunable resonant filters and switches”, IEEE Photonics Technology Letters vol. 14 no. 6 pp. 828-830 (June 2002)).
A “microcavity” is, essentially, a microdisk turned inside-out. Integrated optical microcavities have been used in evanescent-wave spectroscopy (E. Krioukov et al., “Integrated optical microcavities for enhanced evanescent-wave spectroscopy”. Optics Letters vol. 27 no. 17 pp. 1504-1506 (September 2002)).